Communication systems generally include transmitters and receivers which must negotiate a data rate at which encoded data is transferred. The encoded data can be digital or analog data. Typically, the transmitter provides data at a first data rate and increases or decreases the data rate in response to errors associated with the communicated data. The receiver analyzes the received data according to a number of error detection schemes and requests that the data rate be increased or decreased depending upon the number of errors detected.
According to a conventional high frequency (HF) data communication system defined by Standard Agreement 5066 (STANAG 5066 V1.2), communication between the communication units begins at an initial or default data rate. The default data rate is defined in Paragraph C.6.4.1 of STANAG 5066. In addition, an initial or default interleaving level for STANAG 5066 systems is defined in Paragraph C.6.4.1. Paragraph C.6.4.1 of STANAG 5066 states:                All connections on which the data rate or other modem parameters can be controlled shall be initiated at 300 bits per second using short interleaving.        
Therefore, communication systems operating according to STANAG 5066 utilize a relatively low initial data rate and a low throughput interleaving level. For example, a first communication unit operating according to STANAG 5066 provides data at a relatively low data rate (300 bits per second (BPS)) using short interleaving to establish a first leg of communication. The use of relatively low data rate with short interleaving ensures that initial communications are not error prone.
Using this relatively low data rate with short interleaving severely limits the amount of data which can be transferred upon the initial establishment of the link. Thereafter, increased data rates and other interleaving schemes can be negotiated based upon the quality of the channel between the first and second communication units. For example, if the initial communication leg is communicated without any errors, the data rate and the interleaving parameters can be increased to achieve a higher overall transfer rate of data according to paragraph C.1.4 of STANAG 5066. However, this technique requires additional time before information is communicated at its optimal rate.
Thus, there is a need for an initial adaptive data rate algorithm which does not rely on low initial data rate. Further, there is a need for an initial adaptive data rate algorithm which does not rely on a relatively short interleaving parameter. Further still, there is a need for increased throughput between communication units during initial communication.